/**
 * Copyright (C) 2001-2017 by RapidMiner and the contributors
 * 
 * Complete list of developers available at our web site:
 * 
 * http://rapidminer.com
 * 
 * This program is free software: you can redistribute it and/or modify it under the terms of the
 * GNU Affero General Public License as published by the Free Software Foundation, either version 3
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
 * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Affero General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License along with this program.
 * If not, see http://www.gnu.org/licenses/.
*/
package com.rapidminer.gui.tools.syntax;

/*
 * XMLTokenMarker.java - XML token marker Copyright (C) 1998, 1999 Slava Pestov Copyright (C) 2001
 * Tom Bradford
 * 
 * You may use and modify this package for any purpose. Redistribution is permitted, in both source
 * and binary form, provided that this notice remains intact in all source distributions of this
 * package.
 */

import javax.swing.text.Segment;


/**
 * XML Token Marker Rewrite
 * 
 * @author Tom Bradford, Ingo Mierswa
 */
public class XMLTokenMarker extends TokenMarker {

	public XMLTokenMarker() {}

	@Override
	public byte markTokensImpl(byte token, Segment line, int lineIndex) {
		char[] array = line.array;
		int offset = line.offset;
		int lastOffset = offset;
		int length = line.count + offset;

		// Ugly hack to handle multi-line tags
		boolean sk1 = token == Token.KEYWORD1;

		for (int i = offset; i < length; i++) {
			int ip1 = i + 1;
			char c = array[i];
			switch (token) {
				case Token.NULL: // text
					switch (c) {
						case '<':
							addToken(i - lastOffset, token);
							lastOffset = i;
							if (SyntaxUtilities.regionMatches(false, line, ip1, "!--")) {
								i += 3;
								token = Token.COMMENT1;
							} else if (array[ip1] == '!') {
								i += 1;
								token = Token.COMMENT2;
							} else if (array[ip1] == '?') {
								i += 1;
								token = Token.KEYWORD3;
							} else {
								token = Token.KEYWORD1;
							}
							break;

						case '&':
							addToken(i - lastOffset, token);
							lastOffset = i;
							token = Token.LABEL;
							break;
					}
					break;

				case Token.KEYWORD1: // tag
					switch (c) {
						case '>':
							addToken(ip1 - lastOffset, token);
							lastOffset = ip1;
							token = Token.NULL;
							sk1 = false;
							break;

						case ' ':
						case '\t':
							addToken(i - lastOffset, token);
							lastOffset = i;
							token = Token.KEYWORD2;
							sk1 = false;
							break;

						default:
							if (sk1) {
								token = Token.KEYWORD2;
								sk1 = false;
							}
							break;
					}
					break;

				case Token.KEYWORD2: // attribute
					switch (c) {
						case '>':
							addToken(ip1 - lastOffset, token);
							lastOffset = ip1;
							token = Token.NULL;
							break;

						case '/':
							addToken(i - lastOffset, token);
							lastOffset = i;
							token = Token.KEYWORD1;
							break;

						case '=':
							addToken(i - lastOffset, token);
							lastOffset = i;
							token = Token.OPERATOR;
					}
					break;

				case Token.OPERATOR: // equal for attribute
					switch (c) {
						case '\"':
						case '\'':
							addToken(i - lastOffset, token);
							lastOffset = i;
							if (c == '\"') {
								token = Token.LITERAL1;
							} else {
								token = Token.LITERAL2;
							}
							break;
					}
					break;

				case Token.LITERAL1:
				case Token.LITERAL2: // strings
					if ((token == Token.LITERAL1 && c == '\"') || (token == Token.LITERAL2 && c == '\'')) {
						addToken(ip1 - lastOffset, token);
						lastOffset = ip1;
						token = Token.KEYWORD1;
					}
					break;

				case Token.LABEL: // entity
					if (c == ';') {
						addToken(ip1 - lastOffset, token);
						lastOffset = ip1;
						token = Token.NULL;
						break;
					}
					break;

				case Token.COMMENT1: // Inside a comment
					if (SyntaxUtilities.regionMatches(false, line, i, "-->")) {
						addToken((i + 3) - lastOffset, token);
						lastOffset = i + 3;
						token = Token.NULL;
					}
					break;

				case Token.COMMENT2: // Inside a declaration
					if (SyntaxUtilities.regionMatches(false, line, i, ">")) {
						addToken(ip1 - lastOffset, token);
						lastOffset = ip1;
						token = Token.NULL;
					}
					break;

				case Token.KEYWORD3: // Inside a processor instruction
					if (SyntaxUtilities.regionMatches(false, line, i, "?>")) {
						addToken((i + 2) - lastOffset, token);
						lastOffset = i + 2;
						token = Token.NULL;
					}
					break;

				default:
					throw new InternalError("Invalid state: " + token);
			}
		}

		switch (token) {
			case Token.LABEL:
				addToken(length - lastOffset, Token.INVALID);
				token = Token.NULL;
				break;

			default:
				addToken(length - lastOffset, token);
				break;
		}

		return token;
	}
}
